Several types of devices have been proposed for protecting vehicle occupants during a crash event. Such devices can be categorized as being either passive devices or active devices.
Passive safety devices deform to absorb energy during a crash event. Passive devices, however, remain in a fixed position during a crash event. Accordingly, there may be a relatively large distance over which the vehicle occupant may travel during a crash event before encountering a passive device.
Active safety devices are those that deploy during a crash event so that they are positioned relatively close to the vehicle occupants to cushion them. By reducing the distance between the occupant and the safety device, the occupant has less time to travel before encountering the safety device, and more time to decelerate on engaging the safety device, and therefore is likely to sustain less injury. A typical active safety device incorporates an air bag that inflates during a crash event. The air bag is typically a fabric bag that is folded and held in a housing until it is deployed. Air bag devices, however, add complexity and cost to the vehicular subassemblies to which they are added.
For some applications, inflatable active bolsters have been developed to enhance vehicle occupant protection in the event of a vehicle crash. Such bolsters are mounted within a vehicle compartment and include a metal or polymeric hollow chamber and an inflator for injecting a fluid into the hollow chamber. In order to reduce the potential for injuries from impacting the vehicle interior, the inflator is activated upon detection of such an event, and the bolster is inflated to form a cushion.
Inflatable active bolsters are largely comprised of non-moving parts, and are generally quite rugged in construction. Nevertheless, there may be occasions when it becomes necessary to service certain active bolster components, for example the inflator, the electrical harness and/or associated electrical connectors. In general, active bolsters are constructed in a way that does not permit for easy access to the internal components once the active bolster is installed in the vehicle. In fact, active bolster systems have necessitated a more robust mounting methodology as compared to passive bolster systems. While passive bolster systems have generally been installed through the use of suitable clips, the attachment force provided by such clips are insufficient to withstand the deployment loads experienced with active bolsters. As such, inflatable active bolster systems are generally installed in the instrument panel using robust fasteners, for example threaded fasteners. In many instances, active bolster installation is performed on the instrument panel outside the vehicle. Subsequent removal of the active bolster is a tedious and time consuming process as access to the front of the instrument panel is limited.
As such, there exists the need for an alternate active bolster configuration that permits for easier in-vehicle assembly, as well as flexibility and accessibility with respect to periodic servicing.